/**
 * Copyright (c) 2010 by Kevin Bierhoff.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *    1. Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *    2. Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *    3. Neither the names of the authors nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ''AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.googlecode.syper.test.javasyp.logic;

import com.googlecode.syper.anno.Pred;
import com.googlecode.syper.anno.Result;

import edu.cmu.cs.crystal.annotations.FailingTest;
import edu.cmu.cs.crystal.annotations.UseAnalyses;

/**
 * Make sure conditions are assumed in branches.
 * Relies on default null checks.
 * @author kevin
 * @since Sep 4, 2010
 */
@FailingTest(5)
@UseAnalyses("SymbolicChecker")
public class BranchesFail {

	/** don't flip assumptions! */
	public int abs(int i) {
		if (0 <= i) {
			assert i < 0; // check branch assumption
			return i;
		} else {
			assert 0 <= i; // check branch assumption
			return -i;
		}
	}
	
	/** don't flip assumptions! */
	public int min(int a, int b) {
		@Result final int result = a <= b ? a : b;
		Pred.ensures(result == a || a < b);
		return result;
	}

	/** No assumptions in {@code &} operator */
	public boolean evenAndPositive(int a) {
		return 0 < a & isEven(a);
	}

	/** no assumptions in {@code |} operator */
	public boolean evenOrNegative(int a) {
		return a < 0 | isEven(a);
	}

	/** pretends like even test only makes sense on positive numbers */
	private boolean isEven(int a) {
		Pred.requires(0 <= a);
		return a % 2 == 0;
	}
}
